Improvement in safett-valves



W 11W/1 e s s es:

Ny FETES. PHOTO-LITHOGRAPHER, WASH @sind States @anni (dimite,

JAMES LINNARD, OF PHILADELPHIA, PENNSYLVANIA, ASSIGNOR TO HIMSELF, FRAN- CIS I). WORLEY, AND WILLIAM S. HASSELL, OF SAME PLACE.

Leners Parent No. 90,278, dem May is, 1869.

IMPROVEMENT IN SAFETY-VALVES.

The Schedule referred to in these Letters Patent and making part of the same.

To all whom it may consom.-

Be it knownthat I, J AMES LINNARD, of Philadelphia, Pennsylvania, have invented an Improvement in Safety-Valves; and I do hereby declare the following to be a full, clear, and exact description of the same.

M v invention consists of a safety-valve for steamboilers, constructed and operating as fully described hereafter, in such a manner that it cannot be overloaded nor tampered with to a dangerous extent by unauthorized persons. l

In or'der to enable others skilled in the art to make and use my invention, I will now proceed to describe its construction and operation, reference being had to the accompanying drawing, which forms a part of this specification, and in which- Figure l is a vertical sectional view of my improved I safety-valve for steam-boilers;

Figure 2, a transverse vertical section of the same, on the line 1 2, lig. 1;

Figure' 3, a sectional plan view on the line 3-4, fig. I; and

Figure 4, a perspective view, illustrating a modification of my invention.

Similar letters refer to similar parts throughout the several views.

A represents the cast-iron base of the valve, which is secured to a steam-boiler in the usual manner, and extending vertically through this base is a cylindrical opening, a, having at its ripper end a seat, a', upon which rests the valve B.

Upon the wp ofthe valve B, and retained laterally between lugs c c onvthe same, rests an elliptic or other suitable spring, D, upon which is caused to bear a setscrew F, passing through a threaded opening in a yoke, G, the latter being attached, at its opposite ends, to standards H and H', which are iirmly secured to the base A. y l

Links d d, which are hung to the'lugs c of the valve, serve to connect the latter to a lever, J, which is pivoted at a point, f, toan extension of the standard H.

The lever J is cnstructed with an opening in the centre, as best observed in iig. 3, so that it may .pass

arm of a lever, M, which is hung to the standard H, and is provided at the outer end with a suitable handle, i. t

The projecting arm of the operating lever M passes through a slot, j, in a thin metal casing, P, which is bolted, or otherwise secured, to the body A of the valve, and is provided with an escape-pipe, q.

Before securing the easing P to the base of the valve, and thus covering the parts above the same, the set-screw F is so operated as to cause the spring D to bear npon the valve with the requisite degree of pressure, which is determined by means of the steamguage.

When the casing P has been properly secured in its place, nothingwill project beyond the same, except a portion of the operating lever M, by depressing which the valve B may be'raised from its seat, through the medium of the lever J and links d d.

When the valve is thus closed in, and protected by the casing P, it cannot be loaded beyond the point first determined, or tampered with to a dangerous extent by unauthorized persons, the only result caused by the' manipulation of the lever M being the lifting of the valve and a harmless blowing oli' of steam, which, after passing into the casing, would escape through the pipe q.

In place of the lever M, a spindle, passing through a packed bearing, and provided at'its inner end with a cam, or other device, for operating the lever J, may

be employed. (See g. 4.)

I claim as my invention, and desire to secure by Letters Patent'- 1. The combination of the lever J, valve B, and links connecting the lever to the valve, substantially as herein described.

2. The combination of the lever J, valve B, spring D, and links d d, when arranged in respect to the lever" M, or its equivalent, substantially as specified.

In testimony whereof, I have signed my name to this specification, in the presence-of two subscribing witnesses.

- JAMES LINNARD. Witnesses:

J 01am WHITE, E. SMITH. 

